I know there are a lot of variables to this question but do you find that older lifters (over 55) respond better to full body training 2 days a week or focusing on one main lift a day 4 days a week?
It doesn't matter at all - for any lifter. People get so caught up in this stuff, and I totally understand why, but it doesn't matter at all. Just like where you put the bar when you squat, what kind of grip you take on chins/pull-ups, casein vs. whey...I should write an article on this. Just a lot of bickering and ridiculousness. Understand that an "older" lifter has little to do with age; it has more to do with the serious miles that the body has undergone. So biological age isn't as important as how many times your body has gotten it's ass kicked.
Anyway, with an older lifter there are a couple things that need to be addressed/looked at. First is recovery - that is BY FAR the most important issue. I've written numerous things about recovery, its importance and what to do - in fact we have a whole guidelines for what to do for the 5/3/1 program. But whichever program you use, you must follow the basic guidelines of recovery (and no, none of them cost any money or require you to tell a therapist your bad dreams while submerged in cold water). Stress is stress and you have to be able to recover from it regardless if you do full body, etc.
Within the scope of recovery is sleep, diet, mobility/flexibility and aerobic work. The second thing is injuries - usually prior injuries that restrict the lifter. You have to be able to program around and through them. Third is hypertrophy or HYPERtrophy (depending on the accent emphasis) - we lose muscle mass at an alarming rate when we get older. This doesn't mean that you have to be a bodybuilder or anything remotely close. This gets covered even when doing a balanced program. Fourth is understanding the role of assistance work. For an older lifter, assistance is very important as it can allow him/her to work more without a ton of stress to the body. This can be accomplished a variety of ways but needs to be addressed. Assistance work for an older lifter doesn't have to be "normal" exercises, rather movements: agility ladder, jumping rope, cone drills - stuff that gets your body moving in ways it normally wouldn't.
The more you train like an "athlete" (balance, not just lifting) the better, stronger and healthier you will be. Your body is like your brain; you need to challenge it in different ways or you will become physically stupid. Training should be functional (squat, deadlift, press) and also include unfunctional movements - these are things you normally don't do in training or even life that can help you stay healthier (agility, mobility). The latter is done to make the former easier. You don't need to spend more than 10 minutes/day on the unfunctional stuff to reap the benefits. So do whatever program you want - I HIGHLY encourage people to change things up while keeping the same principles. Have some fun. If the effort and principles remain the same, you will thrive.
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